This invention pertains to hot melt sealants and more particularly to those having enhanced mechanical properties at elevated temperatures.
In the field of adhesives, the trend to hot melt systems has been accelerated in recent years. Hot melt systems provide a 100% solids system containing no volatiles, thereby avoiding the air pollution problems encountered with solvent systems. Another advantage giving impetus to the development of hot melt sealant systems is their ability to develop final mechanical properties almost immediately after application. However, these final mechanical properties are limited because of the limitations required for the application of the adhesive in a melt state to a particular substrate. The high temperature final properties are even more limited as they approach the hot melt systems application temperature. For example, adhesion and lap shear strengths at temperatures in service ranges of about 125.degree. F. (51.7.degree. C.) are generally unattainable with presently available not melt sealant systems. To further complicate the problem these hot melt sealants should also exhibit good low temperature properties without detracting from ease of applicability or high temperature properties.